Feasibility of dexmedetomidine in facilitating extubation in the intensive care unit

Background: Spontaneous breathing trials (SBT) and intermittent mandatory ventilation (IMV) are common techniques utilized to expedite the ventilator weaning process. These techniques often require the reduction and/or discontinuation of sedatives and analgesics. Reducing these medications can lead to agitation and the inability to conduct SBTs or weaning by IMV. Adding dexmedetomidine (dex), a potent alpha-2-adrenergic receptor agonist that possesses sedative, anxiolytic and analgesic effects without causing significant respiratory depression, may facilitate extubation in these patients. Objective: To assess the feasibility of adding dex to facilitate extubation in a group of difficult-to-extubate patients secondary to agitation. Methods: Mechanically ventilated patients who were deemed difficult to wean and extubate secondary to agitation were evaluated for dex therapy. Inclusion criteria were location in an intensive care unit, intubated and mechanically ventilated, required IV sedation, deemed suitable by unit criteria for weaning and extubation within 24 h of dex initiation, previous attempts at weaning sedation and/or analgesia resulted in agitation causing either severe patient ventilator dyssynchrony, prolong need for intubation, or an inability to conduct a successful SBT. Additional inclusion criteria were unsuccessful use of traditional intravenous agents to control agitation. Recommended dex dosing was a bolus of 1 mu g/kg followed by an infusion of 0.2-0.7 mu g/kg/h. Results: Twenty-five patients were evaluated for dex therapy with 20 meeting the criteria to treat. All had failed prior attempts at weaning. Fourteen of the 20 patients were successfully weaned and extubated and one patient was reintubated within 48 h, giving a 65% success rate. Heart rate trended down after dex initiation in most patients but did not result in the discontinuation of dex in any patient. The addition of dex was associated with minimal changes in mean arterial pressure. Conclusions: Dexmedetomidine was initiated in a group of mechanically ventilated patients who failed previous attempts at weaning and extubation secondary to agitation. After dex initiation, 65% of the patients was successfully extubated. Dexmedetomidine was associated with a reduction in concomitant sedative and analgesic use with minimal adverse effect.